The effect of organic fertilizers (compost, cow manure and poulty manure) and urea on yield and some agronomic characteristics of two forage cultivars of maize (Zea mays L.)

Improving physical structures and stimulating of soil micro-organisms through adding organic fertilizers has led to facilitating the release of nutrients and increasing plant growth. In order to investigate the effect of organic fertilizers (compost, cow and poultry) and urea on some morphological traits and yield components of corn plant, an experimental was carried out in split plot arrangement base on randomized complete block design with three replications in the Torogh station of Khorasan Razavi Agricultural Research and Education Center in 2019-2021. The main plots were urban waste compost organic fertilizer (16 and 32 t.ha-1), cow (24 and 48 t.ha-1) and poultry (9.5 and 19 t.ha-1), urea chemical fertilizer (225 and 450 kg.ha-1) and control (no use any fertilizer) and subplot were two corn cultivars (KSC704 and KSC260). The results showed that the use of organic fertilizers significantly (p≤0.01, p≤0.05) improved diameter and length of cob, dry and wet forage yield. The highest plant height (285 cm) was obtained from the impact of 24 t.ha-1 of cow manure in KSC704 cultivar. Also, the maximum wet and dry biomass (75 and 30.5 t.ha-1, respectively) and the maximum ear length (23.1 cm) was obtained from the effect of 32 t.ha-1 of compost in KSC704 cultivar. The lowest amount of dry matter yield was observed in KSC260 variety and using different levels of urea fertilizer and control treatments. In general, the use of organic fertilizers (compost, poultry and cow manure) showed better results in the KSC704 cultivar than of the KSC260 cultivar in the examined traits. There was a positive and significant correlation between dry forage and height (r = 0.54**), cob length (r = 0.57**) and stem diameter (r = 0.71**). In general, the consumption of maximum 32 tons of compost per hectare in commercial KSC704 cultivar has a significant advantage compared with other treatments.